Internal-combustion engine



. 1,613,990 G. B. GERAU INTERNAL COMBUSTI ON ENGINE Jan. 11 1927.

Original Filed July 1923 Sheets-Sheet l WITNESSES\\ INVENTOR I G. Ger-an, $52 14. c'

A TTORNE YS I Jan. 11, 1927. G" B GERAU INTERNAL COMBUSTION ENGINE Original Filed July 1923 2 Sheets-Sheet 2 6,5. Gard u,

ATTORNEYS Patented 11, 1927.

UNITEDVSTATESI I 1,613,990 PATENT OFFICE.

GEORGE BALDWIN GERAU, OF CASTLE, PENNSYLVANIA, ASSIGNOR OF ONE- EIGHTH TO ALVIN F. MAURER, OF CLEVELAND, OHIO; ONE-EIGHTH TO GEORGE 'ZELLER, OF CLEVELAND, OHIO; ONE-EIGHTH TO CARL GUSTAV WALLGREN, CLAR- ENCE M. S. ANDERSON, AND JENNI E SOPHIA JOHNSON, AND ONE-SIXTEEN'IH TO HERBERT WILLIAM JOHNSON AND HARRY GRANT JOHNSON. 1

inrnnnnn-comnusrron' ENGINE.

Application filed July 26, 1923,.Ser1a1 No. 653,990. Renewed .Tune- 17, 1926.

This invention relates to internal combustion engines. v

The object of the invention is to provide a two-cygl'e engine construction which will rangement'of parts will hereinafter appear in the detailed description to follow.

y In carrying out the invention there is provided a two-cycle engine construction with one or more cylinders, and each cylinder having therein a main pistonand an auxiliary piston or plung'er and means associated therewith, whereby the auxiliary piston will operate in conjunction with the main piston to provide a separate chamber in the cylinder into which explosive gases may he introduced or drawn and also operate to transfer, the explosive gases into the compression or firing chamber of the cylinder after the burnt gases have been expelled from said firing or compression chamber, andthereby insure that a thorough scavenging of the firing chamber will take place and also insure that a sufiicient quantity of fresh explosive gas will be introduced into the firing chamher upon each explosion of the same as is possible with the four-cycle engine of known construction.

The invention is illustrated by way of ex ample in the accompanying drawlngs, in which: Figure 1 is a vertical sectional view taken substantially on the line 1-1 of Figure 4 Figures 2 and 3 are views similarto Fig ure 1, but showing difierent operative positions of the pistons and associated valve mechanism,

Figure 4: is a fragmentary horizontal sectional view taken substantially on the'line .4-4 of Figure 1, and Figure 5 is a sectional View similar to Figure 4 taken on the line 55 of Figure .2, when looking upward. j

' Like reference numerals designate "corresponding parts throughout the several views. Referring to the drawing specifically the engine may comprise a cylinder block which may include the number of cylinders 10 desired, and with these cylinders there ma be cast the upper crank case section'll to w ich there may be secured in the usual manner-a lower crank case section 12. At 13 there is indicated a crank shaft. Upon the one wall of each cylinder there may be provided a protrusion 14 which may be formed with an exhaust passage 15. A tappct valve 16 may be utilized for controlling the exhaust passage 15 and this valve may be provided with an elongated stem 17 which may be supported for longitudinal movement as shown and which may have its lower end rovided with a head 18. Also the stem 17 as associated therewith a spring 19, whereby the valve 16 is normally held in its closed position. A cylinder head 20 may be provided for the cylinders 10 which may carry spark plugs 21, one for each of the cylinders, and

also which may be formed to cover the Valve.

16 in the manner shown. The cylinder head 20, together with the cylinderslO, may be cored in order to provide space for the circulation of a cooling liquid.

Within each cylinder there is positioned a main piston 22 and a plunger or auxiliary piston 23. The auxiliary piston 23 ispositioned upon the inner side of the piston 22 in each instance, as shown. The piston 22 comprises a hollow casting as shown with its inner end formedwith a tapered portion 23, and-also this inner end is provided with a pocket or socket 2a which is formed by the cylindrical protrusion or extension 25. The piston 22 may be provided with the usual packing rings as likewise shown, and a-wrist pin 26 to which there is pivotally connected two connecting rods 27, said connecting rods being spaced as shown and connected to one crank portion of the crank shaft 13 in the usual manner.

The auxiliary piston 23 may comprise' a piston head including a plate portion 28 with a skirt 29 depending therefrom and the skirt carrying the usual, acking rings, as at 30.' The inner side of s 'rt 29 maybe tapered to fit upon the upper end portion 23'of the main piston 22. The plate or 'top portion of the piston 23 has formed there- 'with a downwardly extendin casing 31,

and about this casing there is ormed in the plate portiona plurality of openings 32.

' purpose of this element is to afford a cushionv between the two pistons when brought together, that is, the air within the socket 24 will provide this cushion in an obvious manner. The plate portion 28 of the piston 22 may also be recessed, as at 33, whereby to receive a valve 34, said valve 34 being provlded with a stem, 35 which extends into the casing 31. The upper end of the casing 31 has threaded therein a plug 36 through which the valve stem 35 is slidable and within the casing there is positioned a compression spring 37, said compression spring having its one end secured to the casing and its other end secured to the stem 31 and thereby urge the valve 34 to its seating position.

The piston 23 has further threadedly connected therewith a pair of rods 38 which are of the length shown and which extend downwardly through suitable openings formed in enlargements 39 provided upon the interior surface of the main piston 22. Each rod 38 should also be provided with suitable packing rings 40 and between the lower ends of the rods there is secured a plate 41, said plate and rodsconstituting a lifter for the piston 23. Between the connecting rods 27 there is secured to the crank portion of the crank shaft 13 a cam member 42, said cam member being secured to the crank shaft 13 in any desirable manner and comprising an elongated plate member which tapers to a point 44 at its outer end.

The lower end of each cylinder may be provided with a slot 45 in which there is positioned a lifter element 46, said lifter element being in the form of a plate and comprising an elongated portion 47 which terminates at its one end in alaterally extending' portion 48. This element is rockably supported by the means of a. pin 49. said pin extending transversely of the slot 45 and being disposed in .an elongated slot 50 in the associated lifter element 46. The areuate portion 47 of each lifter has projecting therefrom a pin 51 which is adapted to move in a slot 52 formed in the associated side wall of the upper crank case section 11. A compression spring 53 encircles the pin 51 and is adapted to urge the element 46 inwardly. The free end of the arcuate portion 47 of each lifter element is adapted to engage with the head 18 of the associated exhaust valve stem 17.

Upon one side of the cylinders 10 there may be bolted an intake manifold. generally indicated by the reference character 54 and each cylinder may be provided with an intake opening 55 which is closed by a va ve 56, said valve having a stem 57 suitably supmember has extending inwardly a rounded protrusion 60 which is normally pressed by the spring 59 in the path of the main piston 22. p

Lest it be assunied that the different operating parts associated with a cylinder are in the positions illustrated in Figure 1, that is, the main piston 22 beginning its power stroke, the auxiliary piston or plunger 23 seated upon the main piston 22, the intake valve 56 open and the exhaust valve 16 open.

The intake valve 56 is held open due to the piston 22 engaging with its protrusion or nose 60. This valve is held open against the resistance of its compression spring 59.- The valve member 16 is open due to the fact that when the main piston is at substantially the end of its inward stroke, as shown, the lifter element 46 has arranged itself to permit the opening of the valve 16. As the piston 22 moves downwardly. the crank shaft 13 operating or rotating for this purpose, the cam 42 will engage beneath the lifter plate 41 and elevate the plunger or auxiliary piston 23. The pistons 22 and 23 are now separated and thereby form a space or chamber between them and also as is obvious a partial vacuum will be created in this chamber. This piston 22 after moving downwardly a sufiicient degree will permit the closing of valve 56 and also with this downward movement of the piston 22 the lifter member 46 will be operated to maintain the valve member 16 open. It is thought entirely apparent the manner in which the element 46 operates to lift the valve 16. The piston 22 engages the inner edge of this element and swings the same upon the pivot pin-49 and also urges the same outw ardly withthe result that the free end of its'arcuate portion 47 will press upwardly and thereby engage the head 18 of the valve stem 17 and thus elevate the valve 16.

During this interval the auxiliary piston or plunger is moving upwardly, that is, the cam 42 has engaged beneath the plate 41 and thus lifting the auxiliary piston 23.

With the exhaust valve 16 open the upward movement of the piston 23 expelsthe burnt gases from the firing chamber of the engine cylinder. During the upward movement of the auxiliary piston 23 the valve member 24 is in its seated or closed position. Upon upwardly until each reach the osition illustrated in Figure 3, and at whic time down- 1 intake 0 explosive gases present in -a fourward movement of the iston 23 will occur,

' while the piston 22 wil continue to move upwardly and close the port or opening and with the continued movement of these two pistons the gaseous fuel therebetween will be compressed, thereby elevating the valve 34 and permit the transfer of the gases from. beneath the piston '23 into the upper portion or firing chamber of the cylinder. At the beginning of the power stroke of the piston 22, the two pistons will abut each other, as illustrated-in Figure 1, and at this moment a spark should occur for exploding the gaseous fuel in the upper end or firing chamber of the cylinder and the same cycle of operationwill again be performed as heretofore described.

It is to be noted with the operation of the engineheretofore described that the burnt gases are entirely driven from the firing chamber of each cylinder previous to intro ducing explosive gases .therein and this is obtained through the operation of the auxiliary piston 23, that is,-this piston provides a separate chamber intowhich the gaseousfuel may first be introduced or drawn and then'after the burnt gases are driven from the firin chamber of the cylinder, this gaseous uel is transferred into the firing or compression chamber of-the cylinder. It

is, therefore, apparent that with an engine constructed and'operfled in accordance'with the resent invention the 'same advantages relatingto the expelling of burnt gases and cycle engine may be obtained.

- While I have shown and described the preferred form of my invention, I wish it to be understood that I am aware of the fact that the construction, combination and arrangement of parts may ,,be changed by. those skilled in the art'wi fliout departing from the spirit of the invention, as indicated by the appended claims.-

I claim: I 1. In an internal combustion engine, a cylinder, a main piston, an' auxiliary piston movable within said cylinder, means whereby with the power stroke of the main iston t e auxiliary pistoh will move inward y and operate to expel burnt gases from the firing means whereby said chamber of said cylinder and also operate to establish a vacuum between said pistons,

. a valve operated by the initial portion of the return stroke of the main piston to permit explosive gases to fill the vacuum chamber between the cylinder and said explosive gases compressed with theremainder of the return stroke of the main piston, and

valve means carried by the auxiliary iston adapted to permit said compressed exp osive gasto escape into the explosive chamber.

2. In an internal combustion engine, a cylinder, a iston movable therein, a member arrange to be normally disposed in the path of said piston, means for supporting saidmember whereby when engaged by the piston, the same will be given a bodily biased movement and means whereby said movement of the member may be utilized for actuating a. valve. I

3. In an 1nterna1 combustlon engine, a

cylinder, a piston movable therein, a member arranged to be normally disposed in the path of said piston, means for supporting said member whereby when engaged bysaid piston the same will be-given a combined outward and uward movement, and pward movement may be utilized for actuatlng a valve. I

4. In an internal combustion engine, a cylinder, a piston movable therein, a valve lifter comprising an angularly shapedplate member, means for supporting the plate whereby the same willjbe engaged by the piston and given a bodily biased movement, and means whereby the biased movement of the plate may be utilized for lifting a valve.

5. In an en ine constrriction of the charcylinder and adaptedflto be engaged by the piston within said said valve.

- 6. In an engine 0 the characterdescribed,

cylinder foropening a. cylinder, a pair. "f pistons within the cylinder, one of said pistons being connected,

by a crank rod to' the crank shaft of said engine, a pair of rods slidable through the last-named piston and having their inner ends 'connectedto. the other piston, a .plate between the outer and free ends of said rods,- and a cam member secured upon'the' crank shaft adapted to lift the plate and piston connected therewith during the turnin'g movement of said crank shaft, for the purpose ,described.

' GEORGE BALDWIN GERAUL 

